Modern vehicles have a large number of mechatronic systems in which mechanical, electronic and data-processing components are linked to one another. Mechatronic systems play a major role in the form of control structures in vehicles. Examples are engine management for internal combustion engines, anti-lock braking systems, traction control systems, electronic stability systems, etc. These generally contain a measurement device of this generic type, as is described by way of example in DE 42 35 880 A1, by which sensor signals of at least one sensor element can be evaluated, as well as at least one actuating element with an electrical drive.
If the actuating element is arranged in the immediate vicinity of the sensor element, this results in the problem that the sensor signals which are produced by the sensor element are influenced by electrical and/or magnetic fields which occur in particular when there is a change in the electrical drive for the actuating element, and this results in measurement errors.
In order to solve this problem, it has been proposed in the prior art for the sensor element to be protected by shielding against interference influences on the actuating element, with the disadvantage of the costs incurred in consequence.
It is also known for the sensor element to supply sensor signals, or to be activated, only when there is no change in the electrical drive for the actuating element. However, the functions of the sensor element and of the actuating element must be synchronized for this purpose, and this involves a certain amount of complexity.
Finally, the interference influences of the electrical drive for the actuating element can be compensated for by computation. However, the interference behavior must be known for this purpose, and this may demand considerable computation complexity, depending on the application.
In contrast, the exemplary embodiment and/or method of the present invention is based on the object of further developing a method and an apparatus for detection of a variable parameter of a vehicle of the type mentioned initially, in such a manner that it provides better functional reliability and safety, as well as measurement accuracy, with costs that are as low as possible.
This object is achieved by the methods and systems described herein.